1 files changed, 64 insertions, 0 deletions
diff --git a/2016/aoc13/src/main.rs b/2016/aoc13/src/main.rs
new file mode 100644
index 0000000..2c0e70e
--- /dev/null
+++ b/2016/aoc13/src/main.rs
@@ -0,0 +1,64 @@
+extern crate regex;
+use regex::Regex;
+
+use std::io::BufReader;
+use std::io::prelude::*;
+use std::fs::File;
+use std::collections::HashMap;
+
+fn main() {
+    //let target = (7, 4);
+    let target = (31,39);
+
+    let mut states: HashMap<(i32, i32), u32> = HashMap::new();
+    states.insert((1, 1), 0);
+    let mut moves = 0;
+    while moves < 50 {
+/*        if states.iter().any(|(&state, _)| state == target) {
+            break;
+        }
+*/
+        let new_states: Vec<(i32, i32)> = states.iter().filter(|&(_, &x)| x == moves).flat_map(|(state, _)| available_steps(state)).collect();
+
+        moves += 1;
+
+        for state in new_states {
+            if !states.contains_key(&state) {
+                states.insert(state, moves);
+            }
+        }
+    }
+
+    println!("Moves required: {}", moves);
+    println!("Possible destinations: {}", states.iter().count()); 
+}
+
+
+fn available_steps(current: &(i32, i32)) -> Vec<(i32, i32)> {
+    let &(x0, y0) = current;
+    let mut results = Vec::new();
+    for &(x, y) in [(x0-1, y0), (x0+1, y0), (x0, y0-1), (x0, y0+1)].iter() {
+        if x >= 0 && y >= 0 && !is_wall(x, y) {
+            results.push((x, y));
+        }
+    }
+    results
+}
+
+fn print_map() {
+    for y in 0..10 {
+        for x in 0..10 {
+            print!("{}", if is_wall(x, y) {'#'} else {'.'});
+        }
+        println!("");
+    }
+}
+
+fn is_wall(x: i32, y: i32) -> bool {
+//    let favourite_number = 10;
+    let favourite_number = 1352;
+    let funny_num = x*x + 3*x + 2*x*y + y + y*y + favourite_number;
+    let bin = format!("{:b}", funny_num);
+    let number_of_ones = bin.chars().filter(|&c| c == '1').count();
+    number_of_ones % 2 == 1
+}